A Short History of Dopamine and Levodopa in Parkinson’s Disease

Arvid Carlsson, when learning about his Nobel Prize in 2000, told reporters: I have been thinking about this for 40 years1 — a bold word but perfectly appropriate. Dopamine is the neurotransmitter which plays the major role in the central control of movements, posture, vigilance and cognition, emotions and reward, not to forget sexuality and fertility — this is now textbook knowledge but young Carlsson’s proposal of a transmitter role for dopamine originally was met with mere aggression and utter disbelief. Such had been the influence of neurophysiologists that only acetylcholine, Otto Loewi’s famous ‘Vagusstoff’, with its fast electrophysiological action had been accepted as a chemical transmitter, and neurochemists had a very bad time for adding noradrenaline as a peripheral sympathetic neurohormone — however, both groups immediately joined forces to deny dopamine a right of its own (with very rare exceptions such as K.A. Montagu (M. Sandler, pers. comm.) and H. Blaschko (D.B. Calne, pers. comm.)). Had Carlsson yielded to this pressure, the development of effective anti-Parkinson, anti-psychotic and antidepressant therapies would have started much later and under less favourable conditions. But in this way his observation opened the route towards neuropharmacology, and especially to the fabulous career of dopamine — and to its precursor levodopa which was to become the gold standard for Parkinson therapy.